Nanocomposites Fe₂O₃/PNR loaded partially reduced rGO/GCE as an electrochemical probe for selective determination of uric acid and dopamine

In the paper, a high-performance electrode was reported for the determination of uric acid (UA) and dopamine (DA) by loading nanocomposites Fe₂O₃/poly-neutral red (PNR)/partially reduced graphene oxide (rGO) on glassy carbon electrode (GCE). The nanocomposites Fe₂O₃/PNR/rGO were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR), and electrochemical impedance spectroscopy (EIS). Under the optimized condition, the peak currents of UA and DA showed good linear relationships with their concentrations in the range of 1 × 10^–6 to 1 × 10^–3 mol L⁻¹ and 3 × 10^–7 to 9 × 10^–5 mol L⁻¹, respectively. The recovery rates were 93.0–102.0% and 99.2–104.6% for detecting DA from medical injections and human specimens, including urine and serum, respectively, 95.5–105.0% for UA from urine and serum samples. Obviously, this Fe₂O₃/PNR/rGO/GCE is expected to be used in production quality control and clinical test.